In comparison to Check-In Check-Out schemes (also called Tap-In Tap-Out or Touch-In Touch-Out) using proximity smart cards, where the user has to check in while boarding and to check out while alighting, Be-In Be-Out (BIBO) is the common name for ticketing technologies that detect and register automatically the presence of smart devices (smart phones and tablets are non-limiting examples) in a public transport vehicle. BIBO schemes do not require any user action and are therefore “hands free.”